CVE-2021-34551

PHPMailer before 6.5.0 on Windows allows remote code execution if lang_path is untrusted data and has a UNC pathname.

CVSS v3 8.1 HIGH
CVSS v2.0 5.1 MEDIUM

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

5.1^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:H/Au:N/C:P/I:P/A:P

Exploitability : 4.9 / Impact : 6.4

Access Vector NETWORK

Access Complexity HIGH

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/PHPMailer/PHPMailer/blob/master/SECURITY.md	Issue Tracking Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YRMWGA4VTMXFB22KICMB7YMFZNFV3EJ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FJYSOFCUBS67J3TKR74SD3C454N7VTYM/
https://github.com/PHPMailer/PHPMailer/blob/master/SECURITY.md	Issue Tracking Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YRMWGA4VTMXFB22KICMB7YMFZNFV3EJ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FJYSOFCUBS67J3TKR74SD3C454N7VTYM/

Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:phpmailer_project:phpmailer:*:*:*:*:*:*:*:*

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:33:::::::*
	cpe:2.3:o:fedoraproject:fedora:34:::::::*

History

No history.

Information

Published : 2021-06-16 18:15

Updated : 2026-06-17 03:56

NVD link : CVE-2021-34551

Mitre link : CVE-2021-34551

CVE.ORG link : CVE-2021-34551

JSON object : View

Products Affected

phpmailer_project

phpmailer

microsoft

windows

fedoraproject

fedora

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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